From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793184719; b=RaXf21aoyRv7CrHXQY7m/w6e3b5HTMgBaNyBY2lG7y4MAXnLGiNs9QvHKDGzGysHQsO5 wqa4bMdVCm00dAZDlzbqQoi9Qp7XBG63Vqmg26YyETwpM8iI3bfT3C3+iMN4hr5pOdZZ5 wUXxoBKZDja6lJIFi3nV6Sgf8d88qUW+CWkmx9x2TZDHc9iiBaJAeOjbGVG/jKP5GxCkA 6RbMef9OSYq7+iXH8grxXkdGwzQk47/fmf5c0f7BJhyWAkjNAgPa5y7FhtjQidYwE69f3 85TfpM7c/SA5tgDR/M6BZ/kovgwQzuOXJMQDDdvJVjmMi/59Ka0cs5grRVdrXJJNzQg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793184719; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=7VuPLf/Bn8Nq23p16kdsfk/y2q2DGA/iZ/5CkjspwaQ=; b=xOU5YS6JHc8Wt88iXtTLZ+gbOHWxyfU/ry9gOUinSl1gTNwi3WdMqH20fK/8w7Fu+0H6 F5zx2s0Stdm6lOVDtnAEVacrRaWhdcoX1pKGePLWvISLtuIFTLwrYBt/4IFBhRi7kMMN3 +pLlqOhVE0R4+1JN7kkhfEnfhHob9OAlncvlT2KXc5pnlgr7Wl9a8+9nIlmp0e9/JrirH STajmIzvlkt/yPhi87OJ3VQHbQgzbsveFRBv/WMI25Wo2hnySMxinrT9/06foWBMd2WCL ZVU5HKtUpfkItrpMq5XKJDDz9wN8dRUxMhhb/rmeHQthXB26x1NT2zithJLahuBkXEw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=eBRAr6GD; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 246CB606A31A; Wed, 28 Oct 2026 10:51:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=eBRAr6GD Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72B691F01825; Wed, 28 Oct 2026 10:51:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793184718; bh=7VuPLf/Bn8Nq23p16kdsfk/y2q2DGA/iZ/5CkjspwaQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=eBRAr6GDX4kET2Ek9hYjPmzPxEQW5sR6uvgI4atic8jFUwlYMWDd8wXV59vQEJmDv AlVsHhjlRbPVmM+JsGl8xrOaYMa/vGAAwVCuT88dBN9QT0ocy0iENimUTCUqFwHUzd ZJ/bOQ9MzSg0GY8P6RrZp/Tk7FT655/GKkGHxWGmC8FVsr3NEkAZxuLIuhYNKXJq7s gtsGCJwJ0TMNg9xCqSlNtCcEP8zMBLGU0NmNcNK5ipdk004Tl8X/UpJrcNXB+ouHLi z6snhbni4tuYid2Q8J+rBnNdQbMoCFWI3RPJyEfBuFFC6QvzlP9EPVA54/9BYhrquW L6exRasHRYQtA== Date: Wed, 28 Oct 2026 11:51:48 +0100 From: "Oscar Salvador (SUSE)" To: "David Hildenbrand (Arm)" Cc: Andrew Morton , Gregory Price , Zi Yan , Joshua Hahn , Rakie Kim , Ying Huang , Johannes Weiner , Vladimir Davydov , Michal Hocko , Hugh Dickins , Baolin Wang , Lukas Czerner , Carlos Maiolino , Christian Brauner , Jan Kara , Daniel Verkamp , Jeff Xu , Muchun Song , Oscar Salvador , David Stevens , "Matthew Wilcox (Oracle)" , William Kucharski , Chris Li , Kairui Song , Nhat Pham , Miaohe Lin , Naoya Horiguchi , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Eva Kurchatova , stable@vger.kernel.org, Pedro Falcato , "Kiryl Shutsemau (Meta)" Subject: Re: [PATCH v3 05/15] hugetlbfs: enforce F_SEAL_EXEC in setattr Message-ID: References: <20261028-fixes_shmem-v3-0-4ce3baf2db4b@kernel.org> <20261028-fixes_shmem-v3-5-4ce3baf2db4b@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261028-fixes_shmem-v3-5-4ce3baf2db4b@kernel.org> On Wed, Oct 28, 2026 at 10:55:03AM +0100, David Hildenbrand (Arm) wrote: > From: Eva Kurchatova > > F_SEAL_EXEC is enforced by shmem_setattr(), but hugetlbfs_setattr() does > not check it. As a result, fchmod() can change the execute bits of a > sealed hugetlbfs memfd. > > Use memfd_check_seals_mode() in hugetlbfs_setattr() to reject changes > to execute bits when F_SEAL_EXEC is set. > > This also fixes the memfd_test hugetlbfs SEAL-EXEC subtest, where > fchmod() incorrectly succeeded after applying F_SEAL_EXEC. > > Fixes: 6fd7353829ca ("mm/memfd: add F_SEAL_EXEC") > Cc: stable@vger.kernel.org > Signed-off-by: Eva Kurchatova > Link: https://patch.msgid.link/20260629180247.2343229-1-eva.kurchatova@virtuozzo.com > Acked-by: Pedro Falcato > Acked-by: Kiryl Shutsemau (Meta) > Acked-by: Zi Yan > Tested-by: Gregory Price (Meta) > Reviewed-by: Muchun Song > [ david: use common helper; fixup Fixes:; check only regular files ] > Signed-off-by: David Hildenbrand (Arm) Acked-by: Oscar Salvador > --- > fs/hugetlbfs/inode.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c > index 01c4d6f44ebe..02e0a65d596d 100644 > --- a/fs/hugetlbfs/inode.c > +++ b/fs/hugetlbfs/inode.c > @@ -28,6 +28,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -840,6 +841,13 @@ static int hugetlbfs_setattr(const struct mnt_idmap *idmap, > if (error) > return error; > > + if (S_ISREG(inode->i_mode) && (ia_valid & ATTR_MODE)) { > + error = memfd_check_seals_mode(info->seals, inode->i_mode, > + attr->ia_mode); > + if (error) > + return error; > + } > + > trace_hugetlbfs_setattr(inode, dentry, attr); > > if (ia_valid & ATTR_SIZE) { > > -- > 2.43.0 > -- Oscar Salvador SUSE Labs